Dear Chris,

I tried to download the link on classes. It seems to be disabled. Can you help? ■

Originally Posted by chrisk

This is the correct link to the training classes.

Anyway, the class for Sept are now already fully booked.

Not when I tried it ■

I repaired the links in both of Chris's posts. It is always best to C&P the link directly from the browser command line than from another link. ■

I did review the link and hoped to extend our understanding of DEM-CFD. I do not see anything that we did not solved in 1995.

I was hoping for a better presentation on coupled solid-fluid modeling.

Main LIGGGHTS criticisms, are:

1. Only spherical granular shapes or a few non-spheres (elliptical). We developed non-round clusters in 1995. The cluster have now become truely non-round geometry without combining spherical clusters, and without the coomputational penalties. Our studies have shown spheres tend to consolidate and shear with different behavior than typical rock shapes. Spheres flow where rock shapes plug the chute of the same geometry.

2. Volume of Fluid or Finite Volume was coupled to solids as a dual coupling where CDI completed and published around 2000, as I remember at SAG 2001 we published results with Metso in four major papers. Shortly after we sold a solid-fluid code to Metso in 2001.

3. No fast solid-fluid solver. CDI granular non-round (slabby, angular, cubical, et al.) solids and double coupled fluid-gas have a relatively high speed performance. LIGGGHTS was a candidate for our future, but, it must show a little more muscle.

In contrast, millions of solid particles and highly variable close mesh fluid/gas are now included in the tradenamed "Rocky" (solids) & Rocky-G (Rocky w/Gas)" codes. The code capability is almost unbounded. The code is extremely fast and can use modern hardware to its fullest advantage - Intel 8-way or 12-way & AMD-16 way or higher.

We anticipate LIGGGHTS to also improve in the near-future. We are willing to discuss the future and its many variants to all interested parties. ■

Dear Chris,

You have a very impressive and comprehensive list of installations and problem types.

I made observations from your web illustration. True, this may be unfair - I deduced performance based on illustrations. I would be happy to compare composed problem(s) where we apply each solver for the same problem details - solid and gas.

If you wish, we can compose one problem and you another.

Further, you can elect round and/or triangularized shapes. Clusters can be a third model, higher order non-shapes can also be offered. Each can be directed through an atmospheric gas for a selected period of time.

Each model might take the form of +/-200,000 particles and run for +/-15 seconds. We can do millions if you wish. The gas volume can be a typical chulte volume. We have many chute configurations to offer in AutoCAD. I suggest a ~5 meter drop and 5,000 t/h, bulk density 1500 kg/cm, with rock size distributed by volume: 10% x 150 mm, 20% x 100 mm, 20% x 75 mm, 20% x 50 mm, 20% x 25 mm and 10% 15 mm. I have not counted the size of this model. Other distributions can be used. We can jointly set the parameters for the results:

1. execution time for the 15 second period.

2. illustrate wear regimes on chute liners, belt, and skirts per impact and shear work - wear pattern on all surfaces in log or linear format resolved to a surface mesh of 25 mm right triangle.

3. gas velocities in all chute cavities and exiting skirtboard with sealed sides to belt surface and top. Gas enters with discharge opening and exits end of skirts. No other leak points. Ambient chamber would have to be defined.

4. power to accelerate granular stream to say 5 m/s.

5. Multi-processor computer will be used - maybe Intel 6 way or larger or large AMD.

I hope you win so that we can look for your support, or the right to use your code, on future projects. ■